Previewing the first left of Major League Soccer’s Western Conference final (Sunday, 9 p.m. Eastern), here are the must-knows about Real Salt Lake ahead of their meeting with the visiting Portland Timbers:

Diamonds are forever

It’s not that Jason Kreis’s formation change for leg one of the conference semifinals was completely ineffective. After all, the whole point was to slow down Los Angeles’s counterattack, and to RSL’s credit, the Galaxy’s transition was a relative non-factor during their first hour in Carson. Unfortunately, RSL’s unfamiliarity with the night’s 4-2-3-1 formation left them unable to connect passes into attack, something that gave LA more of the ball and, eventually, most of the first hour’s chances.

Back in Salt Lake, despite the loss of midfielder Ned Grabavoy, RSL went back to their usual diamond midfield and eventually won, a 2-0 victory in which LA’s counter was no more effective than in Carson’s opening hour. While two defensive midfielder-formation may have made sense in theory, the players just couldn’t pull it off. Sometimes, it’s best to ignore the chalkboard and to play your best players where they’re most comfortable. Don’t expect Kreis to do too much experimenting going forward.

Expect Ned Grabavoy back; but what of Sebastián Velasquez?

Quietly, Ned Grabavoy has an excellent season, particularly over the first half of the campaign. The 30-year-old’s ability to take his game to a slightly higher level helped offseason the loss of Will Johnson and compensate for the periodic absences of Luis Gil. On Sunday, he’s expected to return to the lineup, a move that will have the unfortunate consequence of relegating Sebastián Velasquez to the bench.

Four days after having a major impact as a substitute in Los Angeles, Velasquez scored his first professional goal, his header pulling opening RSL’s account on Thursday. Though logically you’d think he goes back to the bench with Grabavoy’s health, he’s playing better than Gil. At least, he’s given Real Salt Lake a needed spark going forward.

Odds are Jason Kreis stays with the players who’ve established themselves as starters, meaning Velasquez goes back to the bench. But given what we saw from him in the last round, the second year pro should have an impact on this series; if not in the starting XI, then in a super sub’s role.

Chris Schuler (left) was limited to 16 appearances in the regular season. In the conference semifinal, the 26-year-old scored the series-winning goal after playing in the middle of a defense that allowed one goal in 210 minutes. (Photo: AP.)

Schuler and Borchers present a new challenge

Portland torched Djimi Traoré on Thursday, with the Seattle left-center half playing a part in all three Timbers goals. Five days earlier, the Malian defender was also at fault for a goal, as was central defense partner Jhon Kennedy Hurtado. The duo’s mistakes were one of the Sounders’ major downfalls.

Portland can’t expect the same leniency from Utah, whose central defenders have been excellent thus far in this postseason. Over two legs against Los Angeles, the only goal RSL conceded was a 24-yard bomb from Sean Franklin, one neither Nat Borchers nor Chris Schuler should have been expected to stop. Constantly stressed over the last 30 minutes in LA, the duo held out, muffling that dangerous Galaxy counter. In Sandy, they kept LA off the board for 120 minutes, with Schuler finding the series-winner in extra time.

Schuler, out for much of the season, is getting some much-deserved attention for his play, but Borchers, a former best XI defender, has been his equal. Together, the duo became MLS’s first to solve the Robbie Keane-Landon Donovan conundrum. They’ll prove much more difficult to beat than Traoré and Hurtado.

Who starts at forward?

It won’t be Álvaro Saborio. The Costa Rican has been ruled out of Sunday’s match with a muscle injury, leaving Jason Kreis with four players to choose from for his two forward set:

Joao Plata is the incumbent of sorts (Saborio’s normal partner), but the Edcuadorian didn’t play a minute against Los Angeles, hampered by a hamstring injury. He made the bench in game two, but …

… with Robbie Findley starting both games against the Galaxy, Kreis may elect to keep the veteran in the starting XI. A member of RSL’s 2009 title-winning team, Findley provides a good bridge to …

Olmes Garcia, the young Colombian coming off the bench on Thursday after failing to make the team in Carson. Only 21 years old, he is the least likely to start on Sunday, with Kreis preferring to us him off the bench.

The true (or true-ist) like-for-like option for Saborío is rookie Devon Sandoval, who can serve as a target man – somebody to provide an outlet from Portland’s pressure.

Plata’s relationship with Saborío is part of the reason the duo often start together, so with the Costa Rican out, Findley may again be preferred. But while Sandoval seems a logical option to complement the former U.S. international, Kreis could still elect to get creative in the absence of his first choice number nine.

The importance of Kyle Beckerman

Beckerman is always important to RSL, but against Portland, his performances could prove vital. As the Timbers seek to press high and create quick turnovers, his ability to retain possession, take advantage of openings, and decide when to do which will play in big part in RSL’s potential success.

Perhaps as important: How Beckerman handles Diego Valeri. Or Darlington Nagbe. Who knows? Depending on Portland’s tactics, either could end up demanding Beckerman’s attention, but with both free to drop deep into midfield to pick up the ball, there’s also the potential for one to open up space for the other.

Communication will be vital. Nat Borchers will have to be sure to pull Beckerman back when players are moving into his space, and Beckerman will have to make sure Grabavoy and Gil are positioned to pick up Portland’s creators as he lets them go. Beckerman can’t contain both but he will be expected to neutralize whomever tries to get the ball in front of RSL’s line.

Clearly, Real Salt Lake have already has some success defending Portland’s stars (undefeated in four against them this year), but with the Timbers clicking as they never have before, Beckerman will be particularly stressed to maintain his normal standard of play.